Abstract
INTRODUCTION: Neutral results from trials assessing mechanical thrombectomy (MT) for medium/distal vessel occlusions (MDVO) suggest the need for better selection criteria in these patients. Tortuous vascular anatomies may negatively influence MT efficacy and safety. PATIENTS AND METHODS: Consecutive patients with middle cerebral artery (MCA)-MDVO (M2/M3) who underwent MT at our center between January 2017 and September 2024 were included. Baseline CTAs were semi-automatically analyzed using an in-house vascular analysis framework. The internal carotid artery (ICA) tortuosity index (TI) and anatomical features of the MCA were extracted. Logistic regression adjusted for intravenous thrombolysis administration and onset-to-puncture time evaluated associations of anatomical features with treatment efficacy and safety endpoints. Primary endpoints were complete recanalization (final eTICI 2c/3) and symptomatic intracranial hemorrhage (sICH). RESULTS: 213 patients (81 years IQR 72-87, 51.2% female) were included. MCA bending length (aOR 0.48 [95%CI 0.27-0.86], p = 0.013), MCA-TI (aOR 0.77 [0.60-0.98], p = 0.032) and ICA-TI (aOR 0.59 [0.36-0.96], p = 0.034) were associated with lower probability of complete recanalization. ICA-TI (aOR 0.51 [0.31-0.84], p = 0.008) and mean MCA diameter (aOR 0.34 [0.13-0.90], p = 0.030) correlated with decreased odds of first-pass recanalization. Large mean MCA diameter was associated with lower likelihood of excellent functional outcome (aOR 0.30 [0.09-0.96], p = 0.042). Regarding safety endpoints, larger diameter at occlusion was associated with sICH (aOR 4.04 [1.03-15.87], p = 0.046), while MCA bending length (aOR 2.47 [1.24-4.92], p = 0.010) was linked to subarachnoid hemorrhage. DISCUSSION: Automatic evaluation of anatomical vascular features may predict safety and efficacy of MT in stroke patients with MCA-MDVO. The value of these features as inclusion criteria for future MCA-MDVO clinical trials should be explored. CONCLUSION: Intracranial vascular tortuosity is associated to poor thrombectomy outcomes in patients with MDVO.